US3589459A - Industrial pallet truck with hydraulic weighing means - Google Patents

Industrial pallet truck with hydraulic weighing means Download PDF

Info

Publication number
US3589459A
US3589459A US826225A US3589459DA US3589459A US 3589459 A US3589459 A US 3589459A US 826225 A US826225 A US 826225A US 3589459D A US3589459D A US 3589459DA US 3589459 A US3589459 A US 3589459A
Authority
US
United States
Prior art keywords
valves
hydraulic system
load support
truck
load
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US826225A
Other languages
English (en)
Inventor
Arthur Frank Harvey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Linde Material Handling UK Ltd
Original Assignee
Lansing Bagnall Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lansing Bagnall Ltd filed Critical Lansing Bagnall Ltd
Application granted granted Critical
Publication of US3589459A publication Critical patent/US3589459A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
    • B62B3/00—Hand carts having more than one axis carrying transport wheels; Steering devices therefor; Equipment therefor
    • B62B3/04—Hand carts having more than one axis carrying transport wheels; Steering devices therefor; Equipment therefor involving means for grappling or securing in place objects to be carried; Loading or unloading equipment
    • B62B3/06—Hand carts having more than one axis carrying transport wheels; Steering devices therefor; Equipment therefor involving means for grappling or securing in place objects to be carried; Loading or unloading equipment for simply clearing the load from the ground
    • B62B3/0618—Hand carts having more than one axis carrying transport wheels; Steering devices therefor; Equipment therefor involving means for grappling or securing in place objects to be carried; Loading or unloading equipment for simply clearing the load from the ground using fluid lifting mechanisms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
    • B62B2203/00—Grasping, holding, supporting the objects
    • B62B2203/50—Grasping, holding, supporting the objects comprising weighing means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62B—HAND-PROPELLED VEHICLES, e.g. HAND CARTS OR PERAMBULATORS; SLEDGES
    • B62B5/00—Accessories or details specially adapted for hand carts
    • B62B5/06—Hand moving equipment, e.g. handle bars
    • B62B5/063—Hand moving equipment, e.g. handle bars for low-lift hand trucks

Definitions

  • the invention relates to industrial pallet or stillage trucks of the kind comprising a body portion having a drive unit and being supported on a number of ground wheels, a load support projecting from the body portion of the truck, and an hydraulic system for raising and lowering the load support through a short distance relatively to the body portion so as to pick up a pallet or stillage beneath which the support is introduced.
  • a truck of the kind referred to is characterized in that there is provided in the hydraulic system an hydraulic pressure sensing device calibrated in units of weight so as to give a direct reading of the weight of the load being carried by the load support, and valve means operable momentarily to place the hydraulic system into communication with exhaust.
  • valve means By momentary operation of the valve means when the load support is in its raised position, the inherent stresses in the system are relieved so that the sensing device gives a true reading of the weight of the load.
  • valve means are arranged, when operated, automatically to place the hydraulic system momentarily into communication with exhaust.
  • the valve means may comprise a normally open valve in series with a normally closed valve, which valves are connected to operate substantially simultaneously whereby the two valves are momentarilyboth open during said operation.
  • Preferably means are provided for operating the normally closed valve independently of the normally open valve for the purpose of placing the hydraulic system into communication with exhaust for a sufi'rcient time to lower the load support.
  • the normally open valve is disposed in the hydraulic system on that side of the normally closed valve nearer to exhaust.
  • the hydraulic pressure indicating device may be connected to a part of the hydraulic system between the two valves whereby the device only indicates the pressure in the system when said valves have been operated.
  • the valves may be electrically operated valves and operated by electric switches ganged together so that the valves are operated substantially simultaneously at the fully raised position of the load support.
  • the electric switches are preferably connected in circuit with a limit switch which is operated when the load support reaches the fully raised position, the circuit being such that operation of the first said switches can only actuate said valves when the limit switch has also been operated by the load sup port reaching its fully raised position.
  • the hydraulic pressure sensing device may comprise an hydraulic pressure gauge mounted on the vehicle in a position in which it is clearly visible to an operator of the truck, which gauge is connected by a conduit to the hydraulic system.
  • FIG. 1 is a perspective rear view of an industrial pallet truck
  • FIG. 2 is a diagram of the hydraulic system of the truck of FIG. 1;
  • FIG. 3 is a similar view to FIG. 1 showing an alternative form of truck
  • FIG. 4 is a diagram showing the hydraulic system of the truck of FIG. 3.
  • FIG. 5 shows the electrical control circuit for the hydraulic valves in the system of FIGS. 3 and 4.
  • the industrial pallet truck comprises a body portion supported on a single steerable drive wheel 9 and having a power unit 11 with direction and speed controls 12 mounted on the end of a control handle 13 pivotally mounted on the upper end of the power unit.
  • a fork structure 14 projects forwardly from the body portion, the fork structure comprising two forks 15 (only one of which is shown) connected by a root portion 16 which supports the casing 17 housing the truck storage batteries.
  • the root portion of the fork structure may be raised and lowered by jacks 18 (one only shown) and the outer ends of the forks are supported by trail wheels 19 connected to the root portion by linkages 20 so that as the root portion is raised the trail wheels are lowered to maintain the fork horizontal.
  • the hydraulic system for operating the jacks 18 comprises a pump 21 operated by an electric motor 22 to feed hydraulic fluid from a reservoir tank 8 through pipes 23 and 24 to the liftingjacks 18. Fluid is delivered from the pump 21 through a nonreturn valve 21a and a relief valve 21b is also associated with the pump.
  • the motor 22 is controlled by a pushbutton 25 on the truck control handle 13.
  • a pushbutton 25 on the truck control handle 13.
  • the forks will rise until they reach their upper position at which a stop on the operating linkage engages a limit switch and stops the motor. In this kind of truck the full range of lift is normally about 6 inches.
  • the forks may be lowered by depressing a second pushbutton 26 on the control handle which button opens a normally closed solenoid valve 27 to allow the hydraulic fluid to return from the jacks 18 to the reservoir tank through conduit 28.
  • a relief valve 33 is connected between the reservoir tank 8 and the junction 30 in the conduit leading to the solenoid valve 27.
  • a pressure gauge 32 having a pointer whose movements are dependent on the pressure of the system.
  • the gauge 32 is mounted on top of the body portion 10 in a position which is readily visible to the operator of the truck.
  • the dial of the gauge is calibrated in units of weight. Therefore, since the pressure in the system varies in accordance with the load being carried on the forks, the gauge 32 will record the weight of the load being carried at any particular moment. It has, however, been found thatit is important to read the gauge when the fork structure is in its fully raised position and the motor 22 has stopped.
  • FIGS. 3, 4 and 5 show such an arrangement.
  • FIG. 3 The pallet truck shown in FIG. 3 is similar to that shown in FIG. 1 except for the arrangement of the hydraulic system and like parts are given like reference numerals in the two FIGS.
  • a further solenoid valve 34 hereinafter referred to as the weighing valve, is disposed between the normally closed solenoid valve 27 and the reservoir tank 8.
  • the valve 34 is normally open.
  • the conduit 31 leading to the pressure gauge 32 is connected to the portion of conduit 35 between the valves 27 and 34.
  • FIG. 5 shows the electric circuit for controlling the valves 27 and 34.
  • the energizing coil of the solenoid valve 27 is indicated at 36 and the coil of the weighing valve 34 is indicated at 37.
  • the energizing coil for actuating the motor 22 and pump 21 is indicated at 38.
  • the valve 27 is controlled by the aforementioned normally open pushbutton switch 26 and the motor is controlled by the aforementioned normally open pushbutton switch 25.
  • the changeover limit switch 4] is the limit switch referred I to earlier which is'operate'd when the load support is brought to itsfully raised position.
  • FIG. 5 shows in full line the position the switch 4! adopts when the load support is in its lowermost position.
  • a weighing switch assembly (operated by a pushbutton .44) which comprises two chart geover switches 42 and 43 which are ganged together so as to operate simultaneously.
  • the full line positions of the switches 42 and 43 are the positions they adopt when the load support is in its lowermost position. In this position the valve 27 is closed and the valve 34 is open. When it is required to raise the load the switch 25 is closed and the coil 38 energized starting the motor 22 so that the pump 21 delivers hydraulic fluid under pressure to the jacks 18. The jacks are therefore extended raising the load until the limit switch 41 is changed over to the dotted line position shown in FIG. 5. This stops the motor and pump.
  • gauge 32 is therefore vented to the reservoir and will no longer give a reading.
  • the coil 36 is brought into circuit with the switch 26 once again so that the load may be lowered if required by actuating the switch 26.
  • One advantage of the invention is that the truck operator is able to check the weight of goods simultaneously to loading the goods into a van or onto a lorry. The two operations are thus combined into a single operation and the operator is readily able to ensure that he does not overload the van or lorry. The above arrangement also ensures that a correct reading of the weight is given and that a false reading is not given due to the inherent stresses in the hydraulic system.
  • An industrial truck comprising: a body portion having a drive unit and being supported on a number of ground wheels; a load support projecting from the body portion of the truck; a hydraulic system for raising and lowering the load support through a short distance relatively to the body portion so as to pick up a load beneath which the support is introduced; a hydraulic pressure sensing device connected in the hydraulic system and calibrated in units of weight so as to give a direct reading of the weight of the load being carried by the load support, the hydraulic system being in communication with a reservoir through a normally open valve connected in series with a normally closed valve, which valves are connected to operate substantially simultaneously so that the normally open valve closes at the same time as the normally closed valve opens, whereby the two valves are momentarily both open during said operation, so that operation of the valves, just before a weight reading is taken, momentarily places the hydraulic system into communication with the reservoir.
  • a truck according to claim 1 wherein means are provided for operating the normally closed valve independently of the normally open valve for the purpose of placing the hydraulic system into communication with the reservoir for a sufficient time to lower the load support.
  • a truck according to claim 1 wherein the hydraulic pressure sensing device comprises an hydraulic pressure gauge mounted on the vehicle in a position in which it is clearly visible to an operator of the truck, which gauge is connected by a conduit to the hydraulic system.
  • a truck according to claim 1 wherein the normally open valve is disposed in the hydraulic system on that side of the normally closed valve which is nearer to the reservoir.
  • a truck according to claim 4 wherein the hydraulic pressure indicating device is connected to a part of the hydraulic system between the two valves whereby the device only indicates the pressure in the system when said valves have been operated.
  • valves are electrically operated valves and wherein the valves are operated by electric switches ganged together so that the valves are operated substantially simultaneously at the fully raised position of the load support.
  • a truck according to claim 6 wherein said electric switches are connected in circuit with a limit switch which is operated when the load support reaches the fully raised position, the circuit being such that operation of the first said switches can only actuate said valves when the limit switch has also been operated by the load support reaching its fully raised position.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Forklifts And Lifting Vehicles (AREA)
  • Handcart (AREA)
US826225A 1968-05-20 1969-05-20 Industrial pallet truck with hydraulic weighing means Expired - Lifetime US3589459A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2394368 1968-05-20

Publications (1)

Publication Number Publication Date
US3589459A true US3589459A (en) 1971-06-29

Family

ID=10203836

Family Applications (1)

Application Number Title Priority Date Filing Date
US826225A Expired - Lifetime US3589459A (en) 1968-05-20 1969-05-20 Industrial pallet truck with hydraulic weighing means

Country Status (11)

Country Link
US (1) US3589459A (enrdf_load_stackoverflow)
JP (1) JPS5011666B1 (enrdf_load_stackoverflow)
BE (1) BE733305A (enrdf_load_stackoverflow)
CH (1) CH492635A (enrdf_load_stackoverflow)
DE (1) DE1925680B2 (enrdf_load_stackoverflow)
DK (1) DK128730B (enrdf_load_stackoverflow)
FR (1) FR2008939A1 (enrdf_load_stackoverflow)
GB (1) GB1264797A (enrdf_load_stackoverflow)
IE (1) IE32909B1 (enrdf_load_stackoverflow)
NL (1) NL6907671A (enrdf_load_stackoverflow)
SE (1) SE348448B (enrdf_load_stackoverflow)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982002024A1 (en) * 1980-12-16 1982-06-24 Persson Lars E An electronic weighing device for pallet-lifting apparatuss
US6390751B2 (en) 1998-10-07 2002-05-21 Cascade Corporation Adaptive load-clamping system
US6439826B1 (en) 1998-10-07 2002-08-27 Cascade Corporation Adaptive load-clamping system
US20040031627A1 (en) * 2000-09-27 2004-02-19 Gerard Falcou Device for weighing an object by lifting
US20040140136A1 (en) * 2002-10-12 2004-07-22 Simons Gerald S. Hand truck weighing device and weighing method
US6843636B2 (en) 1998-10-07 2005-01-18 Cascade Corporation Adaptive load-clamping system
EP1486394A3 (de) * 2003-06-11 2008-04-30 Franz Kahl GmbH Hubwagen, insbesondere Gabelhubwagen
US20080122253A1 (en) * 2006-11-23 2008-05-29 Jungheinrich Aktiengesellschaft Cover panel for a drawbar-controlled ground conveyor on the side facing the drawbar
US20160146660A1 (en) * 2013-06-20 2016-05-26 Intersoft Nexø A/S Method and a device for determining the weight of a load
CN112499524A (zh) * 2020-11-24 2021-03-16 宁波朗科称重设备有限公司 物料升降搬运计量的物流设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK84893D0 (da) * 1993-07-16 1993-07-16 E L M Kragelund A S Hydraulisk styret baere- og gribeindretning, fortrinsvis til brug paa gaffelloeftere

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3035650A (en) * 1957-10-31 1962-05-22 Dallas Lee Batten Scale attachment for hydraulic lifts
US3036664A (en) * 1959-11-09 1962-05-29 Chemetron Corp Indicating systems for vertical lifting apparatus
US3154160A (en) * 1962-06-14 1964-10-27 Allis Chalmers Mfg Co Load indicator for material handling vehicle
US3431992A (en) * 1966-12-16 1969-03-11 Smithkline Corp Lift truck scale

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3035650A (en) * 1957-10-31 1962-05-22 Dallas Lee Batten Scale attachment for hydraulic lifts
US3036664A (en) * 1959-11-09 1962-05-29 Chemetron Corp Indicating systems for vertical lifting apparatus
US3154160A (en) * 1962-06-14 1964-10-27 Allis Chalmers Mfg Co Load indicator for material handling vehicle
US3431992A (en) * 1966-12-16 1969-03-11 Smithkline Corp Lift truck scale

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982002024A1 (en) * 1980-12-16 1982-06-24 Persson Lars E An electronic weighing device for pallet-lifting apparatuss
US20050104397A1 (en) * 1998-10-07 2005-05-19 Jordan Dean C. Adaptive load-clamping system
US6390751B2 (en) 1998-10-07 2002-05-21 Cascade Corporation Adaptive load-clamping system
US6439826B1 (en) 1998-10-07 2002-08-27 Cascade Corporation Adaptive load-clamping system
US6454511B1 (en) 1998-10-07 2002-09-24 Cascade Corporation Adaptive load-clamping system
US7018159B2 (en) 1998-10-07 2006-03-28 Cascade Corporation Adaptive load-clamping system
US6843636B2 (en) 1998-10-07 2005-01-18 Cascade Corporation Adaptive load-clamping system
US6951988B2 (en) * 2000-09-27 2005-10-04 Airbus France Device for weighing an object by lifting which invalidates a weight measurement reading whenever a detected shear force is too great
US20040031627A1 (en) * 2000-09-27 2004-02-19 Gerard Falcou Device for weighing an object by lifting
US20040140136A1 (en) * 2002-10-12 2004-07-22 Simons Gerald S. Hand truck weighing device and weighing method
US7002083B2 (en) 2002-10-12 2006-02-21 Simons Gerald S Hand truck weighing device and weighing method
EP1486394A3 (de) * 2003-06-11 2008-04-30 Franz Kahl GmbH Hubwagen, insbesondere Gabelhubwagen
US20080122253A1 (en) * 2006-11-23 2008-05-29 Jungheinrich Aktiengesellschaft Cover panel for a drawbar-controlled ground conveyor on the side facing the drawbar
US8056920B2 (en) * 2006-11-23 2011-11-15 Jungheinrich Aktiengesellschaft Cover panel for a drawbar-controlled ground conveyor on the side facing the drawbar
US20160146660A1 (en) * 2013-06-20 2016-05-26 Intersoft Nexø A/S Method and a device for determining the weight of a load
CN112499524A (zh) * 2020-11-24 2021-03-16 宁波朗科称重设备有限公司 物料升降搬运计量的物流设备
CN112499524B (zh) * 2020-11-24 2023-01-06 宁波朗科称重设备有限公司 物料升降搬运计量的物流设备

Also Published As

Publication number Publication date
IE32909B1 (en) 1974-01-09
NL6907671A (enrdf_load_stackoverflow) 1969-11-24
BE733305A (enrdf_load_stackoverflow) 1969-11-03
FR2008939A1 (enrdf_load_stackoverflow) 1970-01-30
GB1264797A (enrdf_load_stackoverflow) 1972-02-23
SE348448B (enrdf_load_stackoverflow) 1972-09-04
DE1925680A1 (de) 1971-04-29
IE32909L (en) 1969-11-20
CH492635A (de) 1970-06-30
DE1925680B2 (de) 1971-12-09
DK128730B (da) 1974-06-24
JPS5011666B1 (enrdf_load_stackoverflow) 1975-05-02

Similar Documents

Publication Publication Date Title
US3589459A (en) Industrial pallet truck with hydraulic weighing means
US2564002A (en) Power-driven material handling truck
US4093091A (en) Load moment sensing system for lift trucks
US4505111A (en) Hydraulic control system for industrial vehicle
US2899093A (en) morrell
US2916172A (en) Fork lift truck with shiftable ballast
US4300867A (en) Push-pull apparatus for walkie fork truck
US4221530A (en) Force-moment compensating apparatus
US3352569A (en) Industrial trucks
JPH0636076Y2 (ja) ハンドリフトトラック
US5285020A (en) Control system for weighing of load in hydraulically operated lift assembly
US2910204A (en) Industrial lift truck
US4231450A (en) Overload warning system
US3896956A (en) Round bale loader for pickup truck
US2706062A (en) Industrial truck
CA1054979A (en) Combined lift-pallet truck
US4274795A (en) Load carrying vehicles
US3394770A (en) Industrial trucks
US2738087A (en) Fork lift truck
US3911679A (en) Closed center hydraulic system with pump and accumulator output for high speed lift
US4007847A (en) Interlock arrangement for use with sideloader fork lift truck
US3165217A (en) Lift truck with suction counterpoise
US3907141A (en) Operator{3 s station optionally stationary or elevated
US2767394A (en) Tipping moment indicator for lifting trucks
US4168934A (en) Lift truck overload protective circuit having override feature